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901.
Paulo Maurício Bianor Valente Isabel Chagas 《International Journal of Science and Mathematics Education》2017,15(3):527-543
The concepts and instruments required for the teaching and learning of geometric optics are introduced in the didactic process without a proper didactic transposition. This claim is secured by the ample evidence of both wide- and deep-rooted alternative concepts on the topic. Didactic transposition is a theory that comes from a reflection on the teaching and learning process in mathematics but has been used in other disciplinary fields. It will be used in this work in order to clear up the main obstacles in the teaching-learning process of geometric optics. We proceed to argue that since Newton’s approach to optics, in his Book I of Opticks, is independent of the corpuscular or undulatory nature of light, it is the most suitable for a constructivist learning environment. However, Newton’s theory must be subject to a proper didactic transposition to help overcome the referred alternative concepts. Then is described our didactic transposition in order to create knowledge to be taught using a dialogical process between students’ previous knowledge, history of optics and the desired outcomes on geometrical optics in an elementary pre-service teacher training course. Finally, we use the scheme-facet structure of knowledge both to analyse and discuss our results as well as to illuminate shortcomings that must be addressed in our next stage of the inquiry. 相似文献
902.
Massimo Ciuffo Jane Myers Massimo Ingrassia Antonio Milanese Maria Venuti Ausilia Alquino Alice Baradello Giacomo Stella Antonella Gagliano 《Reading and writing》2017,30(8):1667-1686
The silent reading fluency is not an observable behaviour and, therefore, its evaluation is perceived as more challenging and less reliable than oral reading fluency. The present research is aimed to measure the silent reading speed in a sample of proficient students, assessed by an original silent reading fluency task, based on behavioural indicators of the silent reading speed. A total of 325 high school and university skilled students (age range 14–23 years) have been assessed using 3 tasks aimed to evaluate the oral reading speed (lists of words, lists of pseudowords and narrative text) and one task aimed to measure the silent reading speed. The average silent reading speed in our sample was around 12.5 syll/sec, almost double than the oral reading speed rate. The silent reading speed had an increase from 9.13 to 12.38 syll/sec from the first year of high school (ninth grade) to the fifth year of University. Conversely, the oral reading speed remained substantially unchanged for the entire academic course. Our results showed that the reading fluency in silent mode tends to increase up to the last years of University and it may be considered the most rapid and efficient reading mode. This study highlights the importance of including both silent and oral reading modes in the assessment of the older students and young adults, since silent reading is the main reading mode for proficient readers. 相似文献
903.
Tayfun Tuna Jaspal Subhlok Lecia Barker Shishir Shah Olin Johnson Christopher Hovey 《Journal of Science Education and Technology》2017,26(1):82-99
Videos of classroom lectures have proven to be a popular and versatile learning resource. A key shortcoming of the lecture video format is accessing the content of interest hidden in a video. This work meets this challenge with an advanced video framework featuring topical indexing, search, and captioning (ICS videos). Standard optical character recognition (OCR) technology was enhanced with image transformations for extraction of text from video frames to support indexing and search. The images and text on video frames is analyzed to divide lecture videos into topical segments. The ICS video player integrates indexing, search, and captioning in video playback providing instant access to the content of interest. This video framework has been used by more than 70 courses in a variety of STEM disciplines and assessed by more than 4000 students. Results presented from the surveys demonstrate the value of the videos as a learning resource and the role played by videos in a students learning process. Survey results also establish the value of indexing and search features in a video platform for education. This paper reports on the development and evaluation of ICS videos framework and over 5 years of usage experience in several STEM courses. 相似文献
904.
Alejandra J. Magana Sadhana Balachandran 《Journal of Science Education and Technology》2017,26(3):332-346
Electromagnetism is an umbrella encapsulating several different concepts like electric current, electric fields and forces, and magnetic fields and forces, among other topics. However, a number of studies in the past have highlighted the poor conceptual understanding of electromagnetism concepts by students even after instruction. This study aims to identify novel forms of “hands-on” instruction that can result in representational competence and conceptual gain. Specifically, this study aimed to identify if the use of visuohaptic simulations can have an effect on student representations of electromagnetic-related concepts. The guiding questions is How do visuohaptic simulations influence undergraduate students’ representations of electric forces? Participants included nine undergraduate students from science, technology, or engineering backgrounds who participated in a think-aloud procedure while interacting with a visuohaptic simulation. The think-aloud procedure was divided in three stages, a prediction stage, a minimally visual haptic stage, and a visually enhanced haptic stage. The results of this study suggest that students’ accurately characterized and represented the forces felt around a particle, line, and ring charges either in the prediction stage, a minimally visual haptic stage or the visually enhanced haptic stage. Also, some students accurately depicted the three-dimensional nature of the field for each configuration in the two stages that included a tactile mode, where the point charge was the most challenging one. 相似文献
905.
Michael S. Kofoed 《Research in higher education》2017,58(1):1-39
In the United States, college students must complete the Free Application for Student Federal Aid (FAFSA) to access federal aid. However, many eligible students do not apply and consequently forgo significant amounts of financial aid. If students have perfect information about aid eligibility, we would expect that all eligible students complete FAFSA and no aid would go unclaimed. Using data from the National Postsecondary Student Aid Survey, I estimate a multinomial logit model which controls for all variables that contribute to aid eligibility and other student characteristics that may deter FAFSA completion. I find that students who are lower middle income, white, male and independent from parents are less likely to complete FAFSA even when they are eligible for aid. Using propensity score matching, I find that each year applicants forgo $9,741.05 in total aid (including grant and loan aid) which includes $1,281.00 of Pell Grants, $2,439.50 of the balance subsidized student loans, $1,986.65 of the balance of unsubsidized student loans, and $1,016.04 of institutional grants. These aid totals aggregate to $24 billion annually. 相似文献
906.
Students filling out the FAFSA list colleges and universities where they wish their data, sent. Until recently, colleges were provided this list, and the practice was suspended, given concerns that colleges were using the list to strategically allocate aid. Using the, 2011–2012 NPSAS, we analyze student financial aid packages to determine if list position, affects aid. We find little evidence that it does. 相似文献
907.
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910.
Katherine I. Martin 《Reading and writing》2017,30(2):279-298
Orthographic knowledge, the general ability to learn, store, and use information about the orthographic form of words (Stanovich & West, 1989), is a crucial skill for supporting literacy. Although the development of first language (L1) orthographic awareness is impacted by the characteristics of a learner’s L1 writing system, relatively little is known about what impact the L1 may have on second language (L2) orthographic awareness. In this study, English language learners from three L1s (French, Hebrew, Mandarin Chinese), plus L1 English speakers, were tested on their English spelling knowledge using a word-pseudohomophone discrimination task. In addition to allowing for the cross-linguistic comparisons, items were designed to examine whether learners had differing performance on pseudohomophones (misspellings) that targeted vowels versus consonants. Consistent with previous research (e.g., McBride-Chang, Bialystok, Cong, & Li, 2004), the L1 Chinese speakers had the highest (L2) accuracy, followed by the L1 Hebrew and the L1 French speakers. The participants from non-alphabetic languages (Hebrew and Chinese) had significantly lower accuracy on items with misspellings involving vowels compared to consonants, and the size of the vowel-consonant accuracy difference varied substantially across L1 groups. The results demonstrate that the characteristics of a learner’s L1 writing system, particularly the existence of vowel and consonant graphemes, impact the development of L2 orthographic knowledge and sensitivity to different types of word misspellings. 相似文献